Transmission synchronizer



March 2, 1943. P, @RR Re. 22,281

TRANSMISSION SYNCHRONIZR Original Filedhlov. 8, 1939 2 Sheets-Sheet 2 Saw 'fnl/67211272: 1U l I Pczgvzer 0717" Reissues! Mar. 2, 1943 Re. '22,281 t TRANSMIS SION SYNCHRONIZER Palmer Orr, Muncie, Ind., assignor to Borg- Wamer Corporation, Chicago, Ill., a corporation of Illinois Original No. 2,221,892, (latedV November 19, 1940,

Serial No. 303,382, November 8, 1939. Application for reissue January 10, 1941, Serial No.

Z7 Claims.

'I'his application forms a continuation-in-part oi' my application, Serial No. 216,861, led July 1, 1938, i'or transmission synchronizers.

y 'I'he invention relates to transmission synchronizers of the type wherein, preparatory to meshing a pair oi' positive drive elements such as gears or Jaw clutch elements. the rotational speeds ci such positive drive elements are synchronized by axially shifting a synchronizer ring drivingly associated with one of said positive driveelements, into irictional clutching engagement with a friction clutch element drivingly associated with the other of such positive drive elements, and has particular application to that type of synchronizing mechanism wherein axial thrust for developing synchronizing driving engagement between the synchronizer rings and their cooperating cones, is transmitted to the synchronizer ring from the movable positive drive element during the initial stage of shifting o! such element into mesh with its cooperating positive drive element, wherein the driving association of the synchronizer ring with its associated member permits limited oscillatory adjustment of the ring, and wherein the ring is provided with blocker means adapted, in one position ci such oscillatory adjustment, to block axial advance of the mo able positive drive element until synchronization has been eil'ected.

A general object of the invention is to provide an improved arrangement for transmitting thrust from the movable positive drive element to the synchronizer ring. An arrangement widely employed in the past has been one in which a movable jaw clutch element, in the form of an annular sleeve, is splined upon the periphery of a hub element, and is adapted to transmit axialthrust to the synchronizer ring through the medium `of the hub, the latter mounted upon the shaft for axial sliding movement in order to permit such transmission of thrust. A speciilc object of the invention is to substantially reduce the resistance to shifting movement which is oi'- i'ered by the hub. To this end, the invention contemplates an arrangement wherein the hub is axially fixed on its shaft, and thrust is transmitted through the medium oi' a direct thrust connection between the jaw clutch sleeve and the synchronizer ring, adapted in the initial stage of shifting movement oi the sleeve to move the synchronizer ring into engagement with its cooperating cone so as to shift the ring to its blocking position, and under pressure applied to the sleeve, to yield or release so as lto permit addi-- tional shift of the sleeve into clutching engagemissions for passenger automobiles.

ment with a coacting clutch element. The shifting oi the synchronizer ring to blocking position and movement oi.' the ring axially for establishing frictional clutching engagement with its cooperating friction clutch element, are provided for by a lost mostion circumferentially oscillating and axially shii'table association between the ring and the hub.

While any type of thrust transmitting means having the characteristics pointed out above may be employed, the invention contemplates, as a speciilc object, to employ an eiilcient, inexpensive and easily assembled arrangement of axially extending bars interposed radially between the hub and the movable Jaw clutch sleeve, the intermediate regions 4of said bars having thrust receiving engagement with the interior of the sleeve and the ends of the bars having abutting engagement with the synchronizer ring.

A more particular object oi' the invention, and one that is highly important is to provide an arrangement of this type which is extremely compact, particularly in an axial direction. There is a very denite restriction in the axial space available for synchronizing mechanism in trans- In order to attain compactness, the synchronizer rings are axially recessed into the hub so that the amount of axial space required for accommodating the synchronizer rings between the hub rim and. the adjacent jaw clutch elements, is reduced to a minimum.

Other objects, the advantages and uses of the invention will become more apparent after reading the following speciilcation and claims, and after consideration of the drawings forming a part of the specification, wherein:

Fig. 1 is an axial sectional view of a synchronizer embodying the invention;

Fig. 2 is a transverse sectional view of the same taken as indicated by the line 2 2 of Fig. 1;

Fig. 3 is a transverse sectional view showing the parts in a difierentposition or operation taken as indicated by the line 3 3 of Fig. 1; f

Fig. 4 is a detailed sectional view taken as indicated by the line 4 4 oi Fig. 2;

Fig. 5 is an axial sectional view of a 'somewhat modiiled form of the invention; Y

Fig. 6 is a transverse sectional view taken on the line 6 8 oi.' Fig. 5;

Fig. 'I is a plan view of the hub assembly taken on the line 1 1 of Fig. 5; and

Fig. 8 is an axial sectional view taken on the line 8 8 oi Fig. 6.

The drawings show two embodiments of the invention which differ considerably in specific details of construction and operation but which both embody the construction, arrangement, and operation which characterize the invention. "I have shown in Figs. 1 to 4 inclusive, a portion of a synchronizing transmission including a torquetransmitting member III.' forming the rear end of the drive shaft of the transmission, and torque-transmitting members driven shaft Il, piloted as at I2 in the member III, andthe .hub member I3 splined as at I4 on the driven shaft II and secured against axial movement by retaining rings I5 and I8; Positive drive connection may be established between the torque transmitting members I and II, or between a reduction geared torque transmitting member I1 and the member II, by an axially movable positive drive element in the form of a jaw clutch sleeve I8, adapted to be shifted by a shifting fork I9 into positive clutching engagement with clutch teeth .23 formed on the torquetransmitting member Il), or clutch teeth 2l formed on the torque-transmitting member I1. The sleeve I3 is formed with internal clutch teeth 22 in sliding splined engagement with the rim 23 of the hub member I3, and adapted to engage the clutch teeth 20er 2l when moved axially.

The torque transmitting member I1 comprises part of a reduction gear train driven from a pinion 24 on the drive shaft Ill, through the medium of a conventional countershaft gear cluster. Upon being moved into clutching engagement with the clutch teeth 20, the sleeve I3 will receive rotation from the drive shaft III and transmit it directly through the hub I3 to the driven shaft I I. Upon being moved in the opposite direction into clutching engagement with theteeth 2 I the sleeve I 3 willj receive rotation from the torque transmitting member I1 and through the countershaft -just referred to, and will .transmit it through ,the hub4 member I3 to the driven shaft] I.

In order to synchronize a torque-transmitting member I Il or I1 with the hub I3 preparatory to establishing such clutching engagement, I provide a pair of synchronizer rings 25 each including a substantially cylindrical collar portion 25 received in an axially opening annular groove 21 defined withirrthe rim portion 23 of the hub member I3, and a radially outwardly extending v flange 23 formed with blocker teeth 29 ybetween which the teeth 22 of the movable clutch sleeve I3 must pass before the clutching engagement may be had with the clutch teeth 20 or 2|. The opposed ends of the teeth 22 and 29 may be chamfer'ed, as shown at 33 and 3| respectively. The synchronizer rings 25 are provided with internal conical clutch faces 32 adapted to engage external conical clutch faces of clutch elements 33 and 34 respectively, formed on the torque transmitting members Il) and I1.

In order to effect the initial clutching engageincluding theV The form of the invention shown in Figs. to 8 inclusive, has substantially the same identical kparts in the same arrangement as that `described above, and the same reference characters are therefore used to designate such parts. with the exception of the thrust bars 35a, hub" I3a, the shiftable jaw clutch sleeve IBa, and the synchronizer rings 25a which are somewhat modified in construction. Whereas the radially outwardly extending synchronizer ring iianges of Fig. 1 are circumferentially continuous, and embrace the radial edges of the rim portion 23 of the hub,

'f the rings 25a are provided with circumferentially the notches 4 I.

ment between a friction clutch face I3 or 34 and spaced lug portions 23a which project outwardly through notches 4I in the hub rim. In the Fig.

1 form of the invention, such thrust is developed frictionally between a radially outer region of the bar 35 and an axial notch 35 in the sleeve I3, in which such radially outer region is received. In the form of the invention shown in Fig. 5, thrust is transmitted ,througha bar 35a by means of a puppet ball 43 urged into a notch 'teeth 22a of the sleeve I3a, the remaining teeth 22 being of full length.

The blocker teeth 23, or 23a, as the case may be, are adapted to be positioned in blocking relation tg the teeth 22 ofthe Fig. 1 form or 22a of the Fig. 5 form, by biasing of the synchronizer ring to one limit of an, oscillatory lost motion connection with the hub. Such lost motion connection, is, in the Fig. 1 form, formed by the extension of an end of the bar 35 into a notch '33 in the synchronizer ring 25, and, in the Fig. 5

form, by the extension of the lugs 23a through The notches 33 and the notches 4I are of greater extent circumferentially than the bars I5 and the lug 23a respectively, so as to allow limited oscillation of the synchronizer rings relative to the hub. i

Oscillation of a synchronizer ring to full blocking position is effected by the initial clutching engagement between the friction clutch faces. In the event that the synchronizer ring should be in the neutral position shown in Fig. 2 at the beginning of a shift, centrifugal force acting on the bars 35 will develop sufficient frictional engagement between the bars and the notches 36 to cause the bars 'to transmit to the synchronizer ring the slight amount of pressure required for causing the ring to assume the biased position .in which it shifts the thrust bars into binding engagement with the notches 35. The invention also contemplates that the friction faces 32 and the friction faces 33 and 34 respectively may be so closely associated when the movable clutch element is in neutral position, that a iilm of oil may exist between these faces and develop under relative rotation thereof, a slight oil drag tending constantly to rotate the synchronizer ring'toward the limit of its lost motion connection.

' The initial rotation of the ring relative to the hub I3. under thrust from the bars 35, or by oil drag, as described. will be suilicient to rotate the .Y

bars Il into binding engagement with the notchesY II and thus build up the axial thrust sufficiently to ensure the application of sumcient torque to the ring to prevent the ring from being forced back out of its blocking position when the chamfered faces of the teeth 22 or 22a as the case maybe, engage the cooperating chamfered faces of the teeth 2l or Ila respectively.

The thrust transmitting connection is adapted to yield under sumcient axial pressure of the sleeve so as to allow the sleeve to advance into engagement with the blocker teeth 2l. The

. synchronizing operation, which has been started by the thrust transmitted through the thrust bars, may then be completed by thrust transmitted by direct contact of the teeth 22 or 22a against the blocker teeth 2i or Ila as the case may be. The yielding of the thrust connection, in the Fig. 1 form, comprises the slipping of the bars Il in the notches Il. In the Fig. form,

it comprises the recession of the balls 4I against the pressure of the spring Il.

When synchronization is reached, the synchronizer ring will be oscillated back to a neutral position wherein the teeth of the movable jaw clutch sleeve are in register with the spaces between the blocker teeth. As the ring thus approaches the neutral position, the chamfered end faces of the sleeve and blocker teeth will slide upon each other so as-to guide the sleeve teeth gradually into the spaces between the blocker teeth under the continuous urging pressure of the shifting fork Il. I'he shifting of the synchronizer ring back to a neutral position also has the effect, in the Fig. l form, of relaxing the binding engagement of the bars I5 in the slots A Il, thereby relieving the resisting to shifting movement of the sleeve Il.

Completion of synchronization in the form shown in Fig. 5 may be effected by servo-ramps Il, forming the extremities of the notches 4|, against which inclined faces l2 on the lugs lla are adapted to engage when a ring is moved to biased position. The engagement of the faces 5! against the ramps Il increases the axial pressure against the synchronizer ring.

It is contemplated that a synchronizer constructed in accordance with this form of the invention may be self-energizing from the point of initial clutching engagement. That is, as soon as the synchronizer ring makes contact with its cooperating friction cone, the resulting rotation of the ring will cause the inclined faces I2 of the lugs 28a to react against the ramps Il so as to develop suiiicient axial thrust against the ring to complete synchronization without further effort on the part of the operator. The degree of servo action depends on the angularity of the cam surfaces El and l2. If the angle of these surfaces is too steep, there will be relatively little servo action. 0n the other hand, if the angle is too low, the lugs will wedge against the ramps so as to make it unduly diillcult to break the wedging connection. The breaking of the wedging connection is eii'ected by the chamfers on the teeth 29a and 22a when the sleeve. Ila passes through the blocker lugs to a positive clutching position. l y

The invention provides an improved arrangement of parts in a synchronizer. The hub member is axially fixed on the shaft on which it is mounted and thrust is transmitted directly from the shiftable jaw clutch sleeve to the synchro'- nizer ring through the medium of'fthrust elements without the necessity of sliding the hub. 75;

msynshromunnnsnmmmossdmtne axiallyopeningreeessesdefinedwithintherim 0f the hub, making it possible to employ a rim of ample axial dimension and yet maintain axial compactness in the assembly. 'I'he shiftable Jaw clutch sleeve, which carries the drive from one shaft to another, is the outermost element of the assembly and therefore has a maximum diameter. This makes it possible to employ a maximum number of Jaw clutch teeth and thereby minimize the likelihood of failure occurring in the Jaw clutch element. The synchronizer rings, which are operative only a small portion of the total life of the transmission, are of smaller diameter and may be accommodated substantially entirely within the space encircled by the Jaw clutch sleeve. The thrust bars are disposed radially intermediate the sleeve and the synchronizer rings and thus are positioned radially outwardly of the outline of the friction faces. They may. as shown in Fig. 5, overlap the collar portion 28 of the synchroniser ring and engage the radially outwardly extending portions 28a thereof. 'I'hus the bars may be made long enough to ensure smooth sliding in the notches I1, and need not be unduly thick in an axial direction.

In general, the invention achieves compactf ness in an axial direction by teiescoping the various parts within the shiftable jaw clutch sleeve Cand overlapping the parts axially while employing ample space in a radial direction to accommodate such overlapping. This isv an advantage for the reason that the conventional transmismission provides more spare space in a radial y direction than in an axial direction.

. sleeve when the latter is moved axially, thereby to form a positive drive connection between said members, said hub having in its rim an axially extending outwardly opening recess and having an annular recess dened within the inner periphery of said rim, a synchronizer ring having yaportion received within said annular recess and another portion projecting radially outwardly past said axial recess, said synchronizer ring having a lost motion driving connection with the hub, being axially movable relative to the hub into :frictional driving engagement with a cooperating friction clutch element drivingly associated with the other member, and having blocking means adapted when in one of its positions permitted by said lost motion connection, to block axial advance of said movable jaw clutch element and,

when in another of its positions permitted lby said lost motion connection to allow said movable jaw clutch element to complete its axial advance into positive clutching position, and a rigid bar disposed in said axial recess between said sleeve and said hub, axially slidable in said recess, adapted to receive axial thrust from said sleeve, and having an end in abutting relation to the radially outwardly projecting portion of said synvchronilteg ring so as to transmit such thrust to the synchronizer ring.

2. In a synchronizing transmission, a pair oi axially aligned torque transmitting members, a hub axially fixed upon one of said members, said hubhaving a rim defining an axially opening an- 4 nular recess, a movableviaw clutch sleeve having internal splines meshing with external splines on said rim and shiftable axially into positive clutching engagement with a Jaw clutch element drivingly associated with the other member, thus to establish a positive drive connection between said members, a synchronizer ring having a collar portion received in said annular recess, oscillatable and axially shiftable with reference to said hub. adapted under axial pressure to establish a synchronizing frictional driving engagement with a friction clutch element drivingly associated with said other member, and including radially outwardly extending blocker teeth adapted as a result of frictional engagement between said synchronizer ring and said friction clutch element to be osciilated to a position blocking axial advance of .said movable jaw clutch sleeve until synchronization is'substantially complete, and a thrust bai radially interposed between said sleeve and said hub, arranged to receive axial thrust from said sleeve during the initial shifting movement thereof, and having an end region disposed radially outwardly of the friction clutch surfaces and in positive thrust transmitting association with said synchronizer ring so as to transmit such thrust thereto.

3. In a transmission synchronizer, a pair of axially aligned torque transmitting members to be synchronized, a hub axially ilxed upon one of said members, a jaw clutch sleeve encircling said hub, drivingly associated therewith and shiftable axially into positive clutching engagement with a jaw clutch element drivingly associated with the other member, thus to establish a positive drive connection between said members, la synchronizer ring adapted under axial pressure to establish a synchronizing frictional drive connection between said hub and a friction clutch element drivingly associated with said other member, and a thrust bar disposed between said sleeve ingly connected to, and axially movable on said hub, a jaw clutch element drivingly associated with the other member and adapted to be engaged by said movable Jaw clutch element when the latter is moved axially so as to establish a positive drive connection between said members, a synchronizer element having a lost motion driving connection with said hub, adapted to be moved axially into friconal Vdriving engagement with a cooperating friction clutch element drivingly associated with said other member, and including blocking means adapted, when in one of its positions permitted by said lost motion and said hub, having a region adapted to engage and arranged radially outwardly of the friction surface of said synchronizer ring, adapted to receive axial thrust from said sleeve and to transmit thrust to said synchronizer ring.

4. In a synchronizing transmission, a pair of axially aligned torque transmitting members to be synchronized, a hub axially fixed to one of said members, a Jaw clutch sleeve encircling and drivingly associated with said hub and shiftable axially into positive clutching engagement with a jaw clutch element drivingly associated with the other member, thus to establish ,a positive drive connection between said members, a synchronizer ring oscillatable and axially shiftablewith reference to said hub, adapted under axial pressure to establish a synchronizing frictional driving engagement with a friction clutch element drivingly associated with said other member, and including blocker means adapted as a result of frictional engagement between said synchronizer element and said friction clutch element to be shifted into a position blocking axial advance oi' said movable jaw clutch element until synchronization is substantially complete, and thrust means interposed between said sleeve and said hub, adapted to receive axialthrust from said .sleeve during initial shifting movement thereof and having a region in positive thrust transmitting association with said synchronizer ring.

5. A transmission synchronizer comprising a pair of aligned rotatable torque transmitting members, a, hub axially fixed on one of said members, a jaw clutch sleeve encircling, drivconnection, to block axial advance of said movable Jaw clutch element and, when said synchronizer element is in another of its positions permitted by said lost motion connection, to allow said movablejaw clutch element to complete its axial advance into positive clutching position, and means including a thrust bar'disposed between said hub and said sleeve, radially outwardly of the outline of the friction clutch surfaces, axially slidable in the hub, having at an end a thrust transmitting connection with said synchronizer element, and' adapted to receive thrust from the interior of said sleeve and to transmit-the same to said synchronizer element so as to ,effect the initial clutching engagement between said synchronizer element andr its cooperating friction clutch element.

6. A transmission synchronizer comprising a vpair of aligned rotatable torque transmitting members, an axially fixed hub secured upon one of said members, a :law clutch element encircling, drivingly connected to, and axially movable on said hub, a cooperating jaw clutch element drivingly associated with the other member and adapted to be engaged by said movable Jaw clutch element when the latter is moved axially, said hub having an axially opening annular depression, a synchronizer element partially received in said depression, having a lost motion driving connection with said hub, adaptednto be moved axially relative to the hub into fricticnal driving engagement with a cooperating friction clutch element drivingly associated with said rother member, and including blocking means,

.from said sleeve and to transmit such thrust to said synchronizer element so as to eifect initial clutching engagement between said synchronizer element and its cooperating friction clutch element.

7. In a transmission synchronizer, an axially fixed driven torque-transmitting member, a pair of driving members arranged on the opposite sides of and coaxial with said driven member, l

each oi said driving members including a jaw clutch element and a friction clutch element, a `jaw clutch sleeve encircling, drivingly connected to, and axially slidable on said driven member into positive clutching engagement with either of said jaw clutch elements, a pair of synchronizer rings each drivingly associated with and axially movable ,relative to said driven element into frictional driving engagement with a respective friction clutch element, a plurality oi' substantially rigid thrust 'bars disposed between said sleeve and driven member, parallel tothe axis of rotation thereof, adapted to receive axial thrust from said sleeve. and having their ends arranged in axially overlapping relation to portions of said synchronizer rings and radially outwardly thereof and adapted to transmit thrust thereto.

8. In a synchronizing transmission, a torque transmitting member, a synchronizing element drivingly associated therewith and adapted under axial pressure to establish a synchronizing frictional driving connection between said member and a rotatable part to be synchronized therewith, an annular positive drive element encircling said member, drivingly connected thereto and shiftable axially for establishing a positive driving connection between said member and said part, and a thrust bar interposed radially between said positive drive element and said member, and adapted to transmit axial thrust to said synchronizer element for eilecting said frictional driving engagement, said synchronizer element being arranged to have limited circumferential movement with respect to said member and being associated with said bar so as to cause the latter to develop thrust receiving engagement with the movable clutch element as a result of such circumferential movement.

9. In a synchronizing transmission, a pair of axially aligned torque transmitting members, synchronizer and positive drive element drivingly associated with one of said members and movable axially into frctional driving and positive driving engagement respectively, in the order named, with friction and positive drive element carried by the other members, and a thrust element arranged to transmit axial thrust to said synchronizer element, adapted to have limited oscillative movement around an axis parallel to that of said members, and associated with said movable positive drive element so that when oscillated it will develop binding engagementtherewith so as to receive thrust therefrom.

10. In a synchronizing transmission, a torque transmitting member, a synchronizer element drivingly associated therewith and adapted under axial pressure to establish a synchronizing frictional driving connection between said member and a rotatable part to be synchronized therewith. an annular positive drive element drivingly connected to said member and shiftable axially for g a positive driving connection between said member and said part, and a thrust tween said positive drive element and member, extending parallel to the axisof rotation. ar-

'rangedtotransmitaxialthrusttosaidsynchronizer element, and associated with said positive drive element so as to develop binding, thrust receiving engagement therewith when oscillated, said synchronizer element being arranged to have limited circumferential movement relative to said member and being associated with said thrust element so that in such circumferential movement it exerts pressure against said Vthrust element tending to oscillate the same.

12. In a synchronizingtransmission, a torque transmitting member, a synchronizer element drivingly associated therewith and adapted under axial pressure to establish a synchronizing frictional driving connection between said member and a rotatable part to be synchronized therewith, an annular positive drive element encircling said member, drivingly connected thereto and shiftable axially for establishing a positive driving connection between said member and said part', a thrust bar of non-circular cross-section radially interposed between said positive drive element and said member, extending parallel to the axis of rotation, arranged to transmit axial thrust to said synchronizer element, adapted to have limited oscillative movement around its longitudinal axis, having one side region received in a recess in the interior of said positive drive element, and adapted to develop binding. axial thrust receiving engagement in said recess when oscillated, said synchronizer element being adapted to have limited circumferential movement relative to said torque transmitting member and being associated with said bar so that during such circumferential movement it will exert pressure thereagainst tending to oscillate the same.

13. A synchronizing transmission as dened in claim 12, wherein said synchronizer element is provided with means for blocking axial advance of said positive drive element when biased at one limit of said circumferential movement.

114. A synchronizing transmission as deiined in claim 12, wherein said thrust bar is of flattened cross-section having substantially parallel side faces adapted tocoact with side faces of said recess in the developing of said binding engagement element arranged to transmit axial thrust to said synchroniser element, adapted to have limited oscillative movement around an axis parallel to the axis oi' said members, and associated with said positive drive element so as to develop binding axial thrust receiving engagement therewith when oscillated, said synchronizer element being arranged to apply pressure to said thrust element so as to tend to oscillate the same.

11. In a synchronizing ton, a torque transmitting member. a synchronizer element drivingly associated therewith and adapted under axial thrust to establish a synchronizing frictional driving connection between said member and a rotatable part to be synchronized therewith, an annular positivedrive element encircling said member, drivingly connected thereto and shiftable axially for establishing a positive drivin! connection between said member and said part, and a thrust bar radially betherein.

15. A synchronizing transmission as dened in claim 12, wherein said thrust bar is of rectangular cross-section, having substantially parallel side faces, and wherein said recess is slightly wider than the thickness oi' said bar between said faces, and is adapted to coact with said side faces in developing said binding engagement.

16. In a synchronizing transmission, a torque transmitting member, a synchronizer element drivinglv associated therewith and adapted under axial pressure to establish a synchronizing frictional driving connection between said member and a rotatable part to be synchronized therewith, an annular positive drive element encircling said member, drivingly connected thereto and shiftable axially for establishing a positive driving connection between said member and said part, and a flat thrust bar interposed between said positive drive element and said member, with its having a notch loosely receiving a radially innerr region of an end of said bar so as to permit limited circumferential movement of said synchronizer element relative to said member, said synchronizer element being adapted, in approachin g one limit of such circumferential movement to exert pressure against said thrust bar tending to oscillate the same and thereby developing binding engagement of said bar in said recess for receiving thrust from said positive drive element.`

l'I. In a synchronizing transmission, a pair of axially` aligned torque vtransmitting members, a movable jaw clutch sleeve surrounding and drivingly associated with one of said members and adapted to be moved axially into positive clutching engagement with a clutch element carried by the other member, a synchronizer ring drivingly associated with said one member and adapted under axial pressure to establish a synchronizing frictional driving engagement with a coacting fric-y tion clutch element drivingly associated with the other member, and a thrust transmitting bar adapted to transmit thrust to said synchronizer ring, said bar being of flat cross-section disposed within said movable clutch sleeve, its major axis parallel to the axis of said members and its minor axis substantially radial, said sleeve having an interior axially extending recess loosely, receiving a radially outer sideV region of said bar so as tom allow limited oscillating movement thereof vand as a result of such oscillating movement to develop binding engagement with said bar so as to transmit axial thrust thereto, said synchronlzer ring having an axially opening notch receiving a an end of said vbarradially inner extremity of and of such width as to permit limited circumferential movement of said ring, said ring being adapted, when relative rotation ,exists between said ring and its coactingiriotion clutch elements, to exert pressure against said bar tending to oscillate the same so as to develop said binding engagement.

18. A synchronizing transmission as dened in claim,1"l, wherein saidl synchronizer ring is arr nged to have a light driving engagement with i s cooperating friction clutch element when the movable clutch element is inr a neutral position.,v a pair of.

19. In a synchronizing transmission, axially aligned torque transmitting members, a hub axiallyV fixed to one of said members, said hub having a rim defining an axially opening annular recess, a jaw clutch sleeve encircling said l shiftable axially into positive clutching engagement with aI rim, drivingly associated therewith and jaw clutch element drivlngly associated with the other member, thus connection between said members, a synchroniser ring having a collar portion received irLsaid annular recess, oscillatable and axially shiftable with reference to said hub, adapted under axial pressure to establish a synchronizing frictional driving engagementwith aV .friction .clutch element drivingly associated with said other member, and including blocker means adapted-as a result of frictional engagement between said synand said friction clutch element chronizer .ring tobe shifted toa position blocking axial advance of said movable Jaw clutch sleeve until synchronization is substantially complete, and a thrust bar disposed in an axiallvextending recessin said rim, arranged to receive axial thrust from said sleeve, and having an end in positive thrust transmitting association with said .synchroniser 11118. sid synchronizerring being formed -with a 118 Projecting outwardly to establish a. positive driveI am noten 1n said ma, adapted .ts ,coast with the rim `at the extremities of said notch to limit'the oscillative movement of saidv ring, and provided at its radially outerextremity with the aforementioned blocker means.

20. 1n a synchronizing transmission, a pair of axially aligned torque transmitting members, a hub axially nxed to one of said members, said hub having a rim defining an axially opening annular recess, a jaw clutch sleeve encircling said rim, drivingly associated therewith and shlftable axially into positive clutching engagement with a jaw clutch element drivingly associated with the other member, thus connection between said members, a synchroniser ring having a collar portion received in said annular recess, oscillatable and axially shiftable with reference to said hub, adapted under axial pressure to establish a synchronizing frictional driving ,engagement with a friction clutch element drivingly associated with saidzother member, and including blocker means adapted as a result of frictional engagement between said synchroniser ring and saidiriction clutch element to be shiftedl to a position blocking axlaladvance of said movf able jawfclutch sleeve, until vsynchronization is a synchronizing in Aari axially extending recess in saidrim',ar ranged to receive axial thrust from said sleeve. and having an end in `positive being provided with a radiallyextendlng .notch and said synchronizerring including a lug extending radially outwardly throughsaid notch and formed with teeth constituting said blocker means, and wherein said sleeve is- 'formed with internal splines in splinedengagement with said rim and adapted to be engaged by said blocker teeth.

21. In a synchronizing mechanism for motor vehicle transmissions, coaxial driving members each carrying a set of clutch teeth and a friction clutch element. means drivingly connecting said memberstogether for rotation hai; different speeds, a driven member adapted to selectively receive a drive from said driving .members,'a hub structure, means mounting said hub structure on said`drlv`en member for rotation therewith but preventing movement of said4 hubI structure axially of said driven member, a shiftdevice driven with said hub structure 'and having clutch teeth adapted to selectively clutch withsaid sets of clutch teeth,

control structure between each of said driving members and said hub structure, cach of said control structures having a friction clutch part engageable with one of said friction clutch .elements and a stop for controlling shift of said'shift device. means drivingly connecting said control structures wit-h said hub mourn grs-lu structure for accommodating axial and rotative movements of said control structures relative to said hub structure, and means releasably oonnecting said shift device with said control structures for selective shift of said control structures by said shift -device to eifect selective engagement of said friction clutch parte respectively with 'said friction Iclutch elements. said releasable connectcoating additional mut of said l "to said control devices for to establish a positive drive thrust transmitting association with said synchronizer ring, said rim mitting shifting movement from' said shift device selectively to said control structures.

23. A synchronizing mechanism for motor vei hicle transmissions according to claim 2i wherein the releasable connecting means comprises an element releasably engaging the interior of said shift device for shift therewith in transmitting shifting movement from said shift device selectively to said control structures.

24. In a transmission synchronizer, a pair of coaxial torque transmitting members to be synchronized, a hub axially fixed upon one of said members, a jaw clutch sleeve encircling said hub, drivingly associated therewith and shiftable axially into positive clutching engagement with a jaw clutch element drivingly associated with the other member, thus to establish a positive drive connection between said members, a synchronizer ring adapted under axial pressure to establish a synchronizing frictional drive connection between said hub and a friction clutch element drivingly associated with said other member, and a thrust element disposed between said sleeve and said hub, radially outwardly of the friction surface of said synchronizer ring, adapted to receive axial thrust from said sleeve and arranged to transmit such thrust directly to said synchronizer ring.

25. In a synchronizing transmission, a pair of coaxial torque transmitting members to be synchronized, a hub axially fixed to one of said members, a jaw clutch sleeve encircling and drivingly associated with said hub and shiftable axially into positive clutching engagement with a jaw clutch element drivingly associated with the other member, thus to establish a positive drive connection between said members, a synchronizer ring oscillatable and axially shiftable with reference to said hub, adapted under axial pressure to establish a synchronizing frictional driving engagement with a friction clutch element drivingly associated with said other member, and including blocker means adapted as a result of frictional engagement between said synchronizer element and said friction clutch element to be shifted into a position blocking axial advance of said movable jaw clutch element until synchronization is substantially complete, and thrust means interposed between said sleeve and said hub. adapted to receive axial thrust from said sleeve during initial shifting movement thereof and having a region in positive thrust transmitting association with said synchronizer ring.

26. In a transmission synchronizer, a driven shaft, a driving member and hub having alignable peripheral clutch teeth, means detachably mounting said hub on said shaft for rotation therewith in a position adjacent said driving member and fixed against axial movement, a jaw clutch sleeve carried by said hub, having internal teeth intermeshing with the hub teeth and shiftable axially thereon, a synchronizer ring confined between said hub and said driving member, having a friction clutch part for engagement with said friction clutch element, having peripheral blocker teeth, alignable with said hub teeth, and having a driving connection with said hub permitting axial shift of said synchronizer ring into frictional driving engagement with said friction clutch element and permitting rotatable shift of said synchronizer ring relative to said hub between a position wherein said blocker teeth are in blocking relation to the teeth of said sleeve and a position permitting said sleeve to advance to a position wherein its teeth establish clutching engagement with the clutch teeth of said driving member, and means releasably connecting said sleeve with said synchronizer ring for transmitting shifting movement from the sleeve to said ring in order to move the latter into engagement with said friction clutch element, said releasable connecting means accommodating said advance of said sleeve to said clutching position.

27. A transmission synchronizer including a driven shaft having a shoulder, a driving member and a hub provided with alignable peripheral clutch teeth, each mounted on the shaft with the driving member rotatable on the shaft and confined between the hub and the shoulder and the hub drivingly connected to the shaft and detachable to permit assembly and removal of the driving member, a jaw clutch sleeve carried bythe hub, having internal teeth meshing with the hub teeth and shiftable axially thereon, means fixing the hub against axial movement on the shaft, a synchronizer ring confined between said hub and said driving member, having a friction clutch part for engagement with said friction clutch element, having peripheral blocker teeth, alignable with said hub teeth, and having a driving connection with said hub permitting axial shift of said synchronizer ring into frictional driving engagement with said friction clutch element and permitting rotatable shift of said synchronizer ring relative to said hub between a position wherein said blocker teeth are in blocking relation to the teeth of said sleeve and a position permitting said sleeve to advance to a position wherein its teeth establish clutching engagement with the clutch teeth of said driving member, and means releasably connecting said sleeve with said synchronizer ring lfor transmitting shifting movement from the sleeve to said ring in order to move the latter into engagement with said friction clutch element, said releasable connecting means accommodating said advance of said sleeve to said clutching position.

PALMER ORR. 

